1. Field of the Invention
This invention relates to a method and apparatus for performing color space conversion, more particularly to a method and apparatus for performing color space conversion between digitized YCbCr color components and digitized RGB color components.
2. Description of the Related Art
Nowadays, due to the growing popularity of multimedia applications, the development of advanced data processing techniques for digital audio data and digital video data has become more and more important. It is noted that, due to the limited bandwidth of the transmission networks and the limited storage spaces of the existing computer systems, digital video data have to be compressed before transmission or storage. Thereafter, the compressed data are decompressed so as to obtain the original digital video data from the storage or transmission media.
Presently, digitized YCbCr components, wherein the Y component represents luminance or picture brightness, the Cb component (B-Y) represents the scaled difference between the blue value (B) and the luminance (Y), and the Cr component (R-Y) represents the scaled difference between the red value (R) and the luminance (Y), are used in known compression algorithms since the digitized YCbCr components occupy less bandwidth when compared to digitized RGB (Red-Green-Blue) components which are obtained by passing analog RGB signals through an analog-to-digital converting means. However, the existing imaging and displaying apparatuses generally use analog RGB signals to represent image. Therefore, the analog RGB signals must initially pass through an analog-to-digital converting means and are then converted into digitized YCbCr components before compression. The digitized YCbCr components are converted into the digitized RGB components after decompression. If necessary, the digitized RGB components are converted into analog RGB signals.
Although there are many conventional techniques for color space conversion, the architecture of the conventional techniques permits conversion in only one mode, that is, either converting YCbCr components to RGB components or converting RGB components to YCbCr components. Additionally, the conventional techniques are expensive due to the large memory requirements thereof. Furthermore, the conventional techniques that use multipliers are relatively expensive and have a relatively slow operating speed.